Compress/melt processor for contaminated plastic waste

ABSTRACT

A compress/melt waste processor includes a frame; a chamber housing having walls which define a chamber therein; a ram movably disposed in the chamber; a sensor which senses pressure applied by the ram; an actuator operatively connected to the ram to move the ram; a chamber hatch upon which the housing is mounted, the chamber housing walls, the ram and the chamber hatch defining a space therebetween; and a device for feeding contaminated plastic waste into the chamber. The apparatus also includes a device for heating the housing walls, the ram and the chamber hatch; a device for cooling the housing walls, the ram and the chamber hatch, a device for detecting temperature of the housing walls, the ram, the chamber hatch and the contaminated plastic waste in the chamber; and a control device for controlling the actuator and the heating and cooling devices. The control device activates the actuator so that the ram applies pressure to the contaminated plastic waste and also activates the heating device such that pressure and heat are concurrently applied to the plastic waste until the plastic waste reaches a predetermined temperature. The control device also activates the cooling device when a predetermined temperature has been reached in order to cool the heated plastic waste.

STATEMENT OF GOVERNMENT RIGHTS

The invention described herein may be manufactured and used by or forthe Government of the United States of America for governmental purposeswithout the payment of any royalties thereon or therefor.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a division of application Ser. No. 08/128,410, filedSep. 30, 1993, now U.S. Pat. No. 5,411,697.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to an apparatus and a method for processingplastic waste which is contaminated with, for example, food, paper, andmetal, into densified blocks in order to reduce the volume of such wasteand the corresponding storage space associated therewith. Moreparticularly, the inventive apparatus and method are directed towardprocessing plastic waste to produce a plastic slug that is suitable forlong term sanitary storage.

2. Description of the Related Art

Navy ships generate plastic waste at a rate of approximately 0.1-0.2pounds per man per day (0.045-0.09 Kg per man per day). This plasticwaste is of very low density, approximately 1.4 pounds per cubic foot(22.4 Kg per cubic meter) and about 60% of this waste is heavilycontaminated with food. Historically, all of this plastic waste has beendischarged at sea, but this method of disposal has been ended due to itsnegative environmental impact.

The types of plastic waste typically encountered on ships are reflectedin Table 1. Thus, any method or apparatus which is used to process suchplastic must be capable of operating when the plastic waste includes avariety of different plastics which can also be contaminated with food,oil, water, metal and other non-plastics.

                  TABLE 1                                                         ______________________________________                                        SOURCES OF SHIPBOARD PLASTIC WASTE                                            TYPE OF PLASTIC     SOURCE                                                    ______________________________________                                        SOFT  CELLOPHANE        FOOD AND CLOTH-                                                               ING PACKAGING                                               POLYETHYLENE-     PACKAGING, TRASH                                            POLYSTYRENE       BAGS, FILM PACKAG-                                                            ING, FILMS                                            HARD  NYLON             MOLDED PARTS                                                POLYETHYLENE      CONTAINERS                                                  TEREPHTHALATE (PET)                                                           POLYETHYLENE      CONTAINERS, MOLD-                                                             ED PARTS                                                    POLYSTYRENE       CONTAINERS, MOLD-                                                             ED PARTS                                                    POLYVINYL CHLORIDE                                                                              PIPING, HOUSINGS                                      FOAM  POLYETHYLENE      PACKAGING                                                   POLYSTYRENE       PACKAGING, PADS                                             POLYURETHANE      PACKAGING, FOAM                                                               CUSHIONS                                              ______________________________________                                    

However, existing technologies for processing and handling plasticwaste, which include containment, pressure, heat, and screw type plasticrecycling extruders, are highly sensitive to the type of plastic beingprocessed and to any water, oil, and/or non-plastic contaminationpresent. Moreover, each of these existing technologies has disadvantagesassociated therewith and all are suited to an open factory environmentversus a confined environment such as on board a ship.

During containment, the plastic waste is placed in a heat shrinkableplastic bag and the ends of the bag are sealed with a heat gun. Thisresults in the sanitary containment of the plastic waste, but does notreduce the volume of the plastic waste.

Pressure techniques such as that provided by a trash compactor canreduce the volume of waste. However, very high pressures in the order of5,000 to 10,000 psi are required to produce an acceptable density level.The pressure compaction method is deficient in that no sterilization ofthe waste stream is provided. That is, while the contaminated mixedplastic waste is compacted to have a reduced volume, it is not in asanitary inert form such that it can be stored for a long period of timewithout creating a health hazard. Thus, the compressed contaminatedplastic must be disposed of in a short period of time. Moreover, whenthe compressed waste (slugs) are handled, they tend to flake apartcreating an unsanitary condition. In addition, based on testingconducted by applicants, it was determined that no amount of pressurecould maintain the slugs in their compressed shape for more than fiveminutes. That is, due to the elastic memory of the plastic waste only amoderate permanent reduction in volume occurs. In order to overcome thisproblem, the compacted plastic waste can be banded immediately aftercompression. However, this requires a subsequent labor intensive step.

Heating the plastic waste and allowing it to cool can increase thedensity (reduce the volume) of the plastic waste. However, extremelyhigh temperatures of approximately 450° F. are required to produce anysignificant reduction in the volume of the plastic waste. Moreover,there is a limit as to how high a temperature can be applied in order toprevent the creation of unpleasant or noxious fumes that can begenerated if oils and other materials begin to burn. Furthermore, evenat 450° F. the density of the heat-formed slug is still less than thatproduced by the compaction technique at 10,000 psi.

Plastic screw type extruding systems, such as those used in the recycledplastics industry, require the plastic waste to be carefully sorted,washed, and dried prior to being processed. These processes are verylabor, time and space intensive. In addition, plastic extruding systemshave not been used for processing plastic heavily contaminated withfood, oil and non-plastic components. Oil, either from machinery spacesor food oil containers, would likely reduce the friction within thescrew type extruder. Such friction is, however, essential for themelting that takes place within the extruding system, and therefore, anyreduction of friction would form a slug of unknown properties.Furthermore, any metal contamination of the plastic waste would likelydamage the extruding system. That is, the screw type extruder requiresvery tight tolerances. A piece of metal, such as a knife, in the plasticwaste being processed would severely damage a screw extruder. Anotherproblem with extruding systems occurs if the processed plastic is wet.The wet plastic can cause a vapor lock such that the plastic streamexiting the extruder would be foam or would have steam explosions.

Consequently, screw type extruding systems require the waste introducedtherein to be sorted and cleaned prior to entering the system in orderto help prevent the above-mentioned problems from occurring. The sortingoperation could be done manually or accomplished by using metaldetectors. In addition, a shredder can be added to the extruder systemto shred the incoming waste such that contaminates are finely ground sothat they no longer threaten damaging the screw extruder. In any event,the use of an extruding system requires extensive and costly preparationof the incoming waste prior to its subsequent processing.

Additional equipment used for municipal waste streams such as balers,are typically very large and provide no means of sterilizing the wastestream without some type of covering or strapping.

It is readily apparent that the prior art lacks a method and apparatuswhich are simple in design and which allow for contaminated mixedplastic waste to be processed into a sanitary inert form such that itcan be stored for a long time without creating a health hazard.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a simply constructed andcompact apparatus for processing mixed plastic contaminated with food,oil, metal and other non-plastics, to produce an end product which iscompact, sanitized and capable of extended storage without creating asanitary problem.

This object is met by providing a compress/melt waste processorincluding a frame; a chamber housing having walls; a chamber hatch uponwhich the chamber housing is mounted, wherein the housing walls and thechamber hatch define a chamber therein; a ram movably disposed in thechamber, wherein the housing walls, the chamber hatch and the ram definea space therebetween; means for feeding contaminated plastic waste intothe space; an actuator operatively connected to the ram to move the ram,wherein the actuator operates to move the ram into contact with thecontaminated plastic waste such that a compaction pressure is applied tothe contaminated plastic waste; means for heating the housing walls, theram and the chamber hatch; means for sensing the compaction pressureapplied by the ram; means for detecting temperature of the housingwalls, the ram, the chamber hatch and the contaminated plastic waste inthe chamber; and control means, responsive to input signals receivedfrom the pressure sensing means and the temperature detecting means, forcontrolling the actuator and the heating means.

The control means controls the actuator and the heating means suchthat 1) at times when the contaminated plastic waste is fed into thespace, the control means controls the actuator to cause the ram to applya first compaction pressure to the contaminated plastic waste within thespace such that the contaminated plastic waste is compacted to form aslug, 2) upon the first compaction pressure being obtained, and whilecontinuing to cause the ram to compact the slug at the first compactionpressure, the control means activates the heating means to heat thehousing walls, the ram, and the chamber hatch to a predeterminedtemperature whereby at least a portion of the slug is melted, 3) uponthe housing walls, the ram, and the chamber hatch reaching thepredetermined temperature, and while continuing to cause the heatingmeans to heat the housing walls, the ram, and the chamber hatch at thepredetermined temperature, the control means controls the actuator suchthat the ram compacts the slug at a second compaction pressure, and 4)upon the slug exceeding a predetermined internal temperature, thecontrol means deactivates the heating means while continuing to controlthe actuator such that the ram continuously compacts the slug until themelted portion of the slug has cooled sufficiently to harden.

It is a further object of the invention to provide a method forprocessing mixed plastic contaminated with food, oil, metal and othernon-plastics, to produce an end product which is compact, sanitized andcapable of extended storage without creating a sanitary problem.

This object is met by providing a method including feeding thecontaminated plastic waste into a chamber defined by a plurality ofwalls; compacting the contaminated plastic waste within the chamber byapplying a compaction pressure thereto, the compacted plastic wasteforming a slug; directly heating all outer surfaces of the slug whileconcurrently continuing compacting of the slug; melting at least some ofthe contaminated plastic waste of the slug due to the heating such thata melted layer forms along all the outer surfaces of the slugencapsulating unmelted portions of the slug within the melted layer;cooling the slug while continuing compacting the slug until the meltedlayer hardens to form a plastic coating at all the outer surfaces of theslug which encapsulates all remaining portions of the slug; and ejectingthe cool slug from the chamber.

Additional objects and advantages of the invention will be set forth inthe description which follows, and in part will be obvious from thedescription, or may be learned by practice of the invention. The objectsand advantages of the invention may be realized and obtained by means ofthe instrumentalities and combinations particularly pointed out in theappended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated and constitute part ofthe specification, illustrate a presently preferred embodiment of theinvention, and together with the general description given above and adetailed description of the preferred embodiment given below, serve toexplain the principles of the invention.

FIG. 1 is a schematic cross-sectional view of the inventive apparatus;

FIG. 2 is a schematic cross-sectional view of the apparatus of FIG. 1during an initial feed step;

FIG. 3 is a schematic cross-sectional view of a second embodiment of theapparatus during an initial feed step;

FIG. 4 is a schematic cross-sectional view of the inventive apparatus ofFIG. 1 during a compact/compress step;

FIG. 5 is a schematic cross-sectional view of the inventive apparatus ofFIG. 1 during a compress/melt step;

Figure. 6 is a schematic cross-sectional view of the inventive apparatusof FIG. 1 during a cooling step; and

FIG. 7 is a schematic cross-sectional view of the inventive apparatus ofFIG. 1 during an ejection step.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In FIG. 1, the compress/melt plastic waste processor 1 is shown asincluding a frame assembly 3 which supports all of the other componentsof the compress/melt plastic waste processor 1. A compress/melt chamberhousing 5 is disposed on top of a chamber hatch 7 to define a chamber 9between the walls 11 of the compress/melt chamber housing 5 and thechamber hatch 7. Chamber 9 has an open end 12 through which mixedplastic waste contaminated with, for example, food, oil, metal and othernon-plastics, can be placed in chamber 9. A compaction ram 13 isoperably connected to a linear actuator 14 such that the actuator 14 canmove the compaction ram 13 within the chamber 9. Thus, the compactionram 13 can be moved into contact with the contaminated mixed plasticwaste in the chamber 9 in order to compress/compact the contaminatedmixed plastic waste against the chamber hatch 7 thereby forming a slug15 (densely packed contaminated plastic waste) out of the contaminatedmixed plastic waste. All of the outer surfaces of the slug 15 are forcedagainst corresponding inner surfaces 16, 17, 18 which are respectiveinner surfaces of the chamber housing walls 11, the compaction ram 13and the chamber hatch 7. The actuator 14 could, for example, be ahydraulic cylinder, a pneumatic cylinder, ball screws, or some othermechanical or electro-mechanical actuator.

The walls 11 of the compress/melt chamber housing 5, the compaction ram13 and the chamber hatch 7 are all controllably heated by heat sources19 which can be embedded or clamped in place on each of theaforementioned structures. Heat sources 19 may be any appropriateheating device capable of heating walls 11, compaction ram 13 and thechamber hatch 7 as, for example, conventional electric resistive heatingelements. In FIG. 1, the heat sources 19 are shown as being embedded inplace. The heat sources 19 could also be in the form of a heat blanket.Alternatively, instead of using electric resistive elements, rings ortubes, having steam or heated fluid therein, can be disposed around orformed in the chamber housing walls 11, the compaction ram 13 andchamber hatch 17. The steam or heated fluid would be heated by aconventional external source and continually circulated to perform therequired heating.

Control of the heating of the walls 11, the compaction ram 13 andchamber hatch 7 can either be manual or automatic. In FIG. 1, acontroller 21, such as a computer, is operatively connected totemperature detecting means such as thermocouples 23, 25 and 27 whichcontinually send a signal, representative of the temperature of thestructure in which they are embedded, to the controller 21.Alternatively, resistive temperature devices (RTU's) or otherappropriate temperature sensing devices can be used instead of or incombination with thermocouples 23, 25 and 27. The controller 21 which isconnected to the heat sources 19 can be programmed to turn the heatsources 19 on and off depending on whether the signals from thethermocouples 23, 25 and 27 are above or below a predetermined value. Inthis manner, the temperature of the walls 11, compaction ram 13 andchamber hatch 7 are controlled.

In a manual mode, the temperature readings from the thermocouples 23,25, 27 could be displayed on a monitor (not shown) such that an operatorcould turn power to the heat sources 19 on and off based on thetemperature readings.

An additional thermocouple 29 can be passed through an opening 31 incompaction ram 13 and secured in place so that it extends outward frominner wall 17 and into slug 15. Thermocouple 29 is operatively connectedto controller 21 and provides a signal thereto which is indicative ofthe approximate temperature at the approximate center of slug 15.

The compaction ram 13, compress/melt chamber walls 11, and chamber hatch7 are all heated during the operation of the compress/melt plastic wasteprocessor as discussed in more detail below, in order to ensure that allof the outer surfaces of the slug 15 which contact a corresponding oneof the inner surfaces 16, 17, 18 are melted during heating.

It is to be noted that upon the melting and subsequent cooling of theplastic waste material within the compress/melt plastic waste processor,the slug 15 is formed with a final hardened shape. The cross-sectionalshape of the compaction ram 13, the compress/melt chamber housing 5 andthe chamber hatch 7 will determine the final shape of the slug 15. Thecross-sectional shape of these components can, for example, be oval,cylindrical, triangular, rectangular or any other desired shape. Thegeometry of the top and bottom faces of the slug will be determined bythe faces of the compaction ram 13 and the chamber hatch 7. Thus, thecompaction ram 13 and the chamber hatch 7 can be manufactured, forexample, to produce flat or cup shaped slugs.

In order to more fully understand the claimed invention, the operationof the apparatus will be described with reference to FIGS. 2-7. Withrespect to the figures, FIGS. 2 and 3 show the apparatus in an initialfeed step, FIG. 4 shows the apparatus in a compress step, FIG. 5 showsthe apparatus in a compress/melt step, FIG. 6 shows the apparatus in acooling step, and FIG. 7 shows the apparatus in an ejection step.

In FIG. 2, the linear actuator 14 has been operated to retract thecompaction ram 13 out of chamber 9. This allows the plastic waste feed33 to be placed in the chamber 9 via the open end 12 in the top of thecompress/melt chamber housing 5. In FIG. 3, a second embodiment is shownin which the compaction ram 13 has been retracted by the linear actuator14 above an opening 35 in one of the walls 11 of the compress/meltchamber housing 5. Thus, the plastic waste feed 33 is inserted into thechamber 9 via the opening 35. A chute 36 is shown as a means for feedingthe plastic waste feed 33 into opening 35. However, any conventionalfeeding means could be used including manual feeding.

As shown in FIG. 4, once a certain amount of plastic waste feed 33 hasbeen placed in the chamber 9, the compaction ram 13 is lowered by thelinear actuator 14 in order to compress the plastic waste feed 33 into aslug 15. This compression step is performed without any heat beingapplied to the chamber hatch 7, the compaction ram 13, and thecompress/melt chamber walls 11. The feed and compress steps of FIGS. 2,3, and 4 are repeated as required until a slug 15 is produced of adesired thickness and at a desired pressure. That is, the plastic wastefeed 33 is compressed until a preferable compaction pressure ofapproximately 40 to 50 psi (2810 to 3515 g/cm²), is achieved. Theactuator 14 is operatively connected to the controller 21. In addition,a means for sensing the compaction pressure, such as a strain gauge 37mounted on a piston rod 39, is also connected to the controller 21. Thecontroller 21 can then control the actuator 14 and the applied pressurebased on feedback from the strain gauge 37. A load cell or other knownpressure measuring device may be used in place of or in combination withstrain gage 37. Alternatively, when actuator 14 is a hydraulic orpneumatic actuator, compaction pressure sensing can be achieved bymonitoring the hydraulic pressure or air pressure therein.

Once a sufficient amount of plastic waste feed has been introduced intothe compress/melt chamber housing 5 in order to produce a slug 15 at thedesired thickness and desired compaction pressure, the compress/meltstep as shown in FIG. 5 begins. During this step, heat is applied to thecompaction ram 13, the compress/melt chamber housing 5 and the chamberhatch 7 via the heat sources 19. The respective inner surfaces 16, 17and 18 of the walls 11, compaction ram 13 and chamber hatch 7 must beheated to a temperature sufficient to melt the bulk of the plastic wasteand to boil off any liquid trapped on the plastic waste, but must not behigh enough to ignite any of the plastic waste nor produce any hazardousfumes associated with the burning of the waste. A temperature range ofapproximately 325° F. to 350° F. (163°-177° C.) is preferable in that itis sufficient to melt the major constituent, polyethylene, of thetypical navy ship and municipal plastic waste stream and to drive thethermal conductivity required to heat the entire slug 15. Moreover, asthe temperature gets closer to 400° F., the burning of oils and paperwill produce smoke while the burning of Teflon, polyurethanes andpolyvinyl chlorides will produce hazardous fumes. As the heat is beingapplied, the linear actuator 14 concurrently moves the compaction ram 13thereby compressing the slug 14 to an even thinner thickness.

At a point when the contaminated plastic waste begins to soften due tothe heat and compaction pressure, the compaction pressure can be reduced(though it is not necessary) to approximately 20 psi (1405 g/cm²). Thereduction in pressure helps to prevent the melted plastic from beingforced into the gap 41 which exists between the compaction ram 13 andthe walls 11 of the compress/melt chamber housing 5. The prevention ofmelted plastic from entering gap 41 is important because during thisprocess, it is desirable to heat all of the slug 15 to a point where allof the moisture contained therein is evaporated. The time required toget heat to the center of the slug 15 is dependent on the temperature ofall of the heated surfaces 16, 17, 18 and on the distance from theheated surfaces 16, 17, 18 to the center of the slug 15. Increasing thecompaction force by the actuator 14 and the compaction ram 13 compressesthe slug 15 thereby reducing the distance to the center of the slug.However, if excessive compaction force is used, the melted plastic wouldfill the gap 41. If the gap 41 is filled by melted plastic, any steamgenerated by the heating of the slug 15 has no means to escape fromchamber 9 in order to allow the slug 15 to dry. Moreover, if meltedplastic enters the gap 41, it will solidify therein during the belowdescribed cooling step. This will produce "flashing" around the edges ofthe finally formed slug 15 which makes it more difficult to remove slug15 from chamber 9 and to stack the slugs 15 during their subsequentstorage.

The compress/melt step continues until the temperature at the center ofthe slug 15 exceeds the boiling point of water, at which time almost allof the moisture in the plastic waste should be evaporated. Thecompress/melt step is further continued to a point where the slug issurrounded by a minimum of a quarter of an inch of a melted plasticlayer. The melted plastic layer is measured as extending from all of theinner surfaces 16, 17, and 18. In a typical Navy mixture of plasticwaste which is primarily made up of polyethylene, polypropylene,polystyrene, and food contaminates, the melted plastic layerencapsulates any unmelted plastic, food and non-plastic materials,including metal pieces, which may be part of the waste.

Once the compress/melt step has been completed, a cooling stepcommences. As shown in FIG. 6, cooling tubes 43 are disposed aroundchamber walls 11, compaction ram 13, and chamber hatch 7, and suppliedwith cooling water or cooling oils in order to cool the respectivecomponents about which they are disposed. The cooling tubes 43 can bemounted to the outside of the component being cooled such as shown inFIG. 6 for the compaction ram 13 and the chamber walls 11, or can beintegrally formed within a component as shown for chamber hatch 7. Thecirculation of the cooling fluid is conventional and will not be furtherdescribed. However, the controller 21 can be used to control the flow offluids by being connected to, for example, a solenoid valve. Additionalcooling techniques such as using forced air or simply allowing coolingto take place passively can be used in lieu of the cooling tubes.

During the entire cooling process, the compaction ram 13 continues toactively compress the slug 15. Cooling continues until the core of theslug is below 212° F. (100° C.) so that if there is any remaining steam,it is condensed thereby preventing any steam explosions when the slug 15is subsequently ejected from the compress/melt chamber. Moreover, theslug 15 is not ejected from the compress/melt chamber until the surfaceof the slug 15 is cooled to a point where the melted plastic layer hashardened and has the majority of its stiffness, thereby preventing theslug from deforming during or after ejection. In the typical mix ofplastics used by the Navy as discussed above, experience has shown thatwhen the temperature of the inner surfaces 16, 17 and 18 have cooled toapproximately 140° F., the required slug stiffness has been achieved. Atthis point in time, the entire slug 15 has a hardened plastic coveringformed from the cooled melted layer.

As shown in FIG. 7, the chamber hatch 7 is slidably mounted on the frame1 and can be moved from a position directly below the compress/meltchamber housing 5 in order to permit the linear actuator 14 to move thecompaction ram 13 to eject the end product slug 15 from thecompress/melt chamber housing 5. The compress/melt chamber housing 5 canbe securely mounted to the frame 3 or movably mounted thereto. In thesituation where the compress/melt chamber housing 5 is fixably mountedin place, it could for example, have wedged grooves therein whichreceive corresponding wedges on the chamber hatch 7 so that when thechamber hatch 7 is slid into place directly below the compress/meltchamber housing 5, the compress/melt chamber housing 5 and chamber hatch7 are securely connected to each other. The movement of the chamberhatch 7 beneath the compress/melt chamber housing 5 could be manuallyaccomplished or can be accomplished through the use of a linearactuator.

If the compress/melt chamber housing 5 is movably mounted to the frame3, the tongue and groove arrangement between the compress/melt chamberhousing 5 and the chamber hatch 7 can be eliminated and, for example anadditional linear actuator could be connected to the compress/meltchamber housing 5 and the frame 3 in order to move the compress/meltchamber housing 5 into and out of contact with the chamber hatch 7.

The vertical apparatus structure shown in the figures could be invertedor could also be horizontally oriented. In either of these configurationthe chamber hatch 7 could be hingedly mounted to the compress/meltchamber housing 5 in a conventional manner such that it opens and closesas a door.

In a preferred embodiment, the respective inner surfaces 16, 17, 18, ofthe compress/melt chamber housing walls 11, the compaction ram 13 andthe chamber hatch 7 are smooth thermally conductive surfaces such as,for example, hard polished aluminum, which helps to prevent the slug 15from sticking thereto. In another embodiment, the hard polished aluminummay be anodized. However, additional conventional non-stick surfaces orcoatings can be used in lieu thereof.

The above-discussed method and apparatus for processing plastic wasteoffers simplicity in design. In its simplest form, the inventiveapparatus incorporates only two moving parts, the compaction ram 13, andthe chamber hatch 7. The controls required to operate the inventiveapparatus are only temperature controls for the heat sources 19 and aforce pressure control for the linear actuator 14. The inventive processhas a very high tolerance to variations in plastic waste content. Theprocess works just as well for mixed plastic waste with non-plasticmixed in, as for a clean and pure plastic infeed as required for devicessuch as extruders. The inventive process greatly increases the infeedplastic waste density such that a 30 to 1 reduction in volume isobtained. Thus, the plastic waste can be efficiently stored and costeffectively transported commercially for recycling or disposal.Moreover, any food waste in the plastic waste feed stream is dehydratedduring the heating of the slug thereby providing a product that can bestored for extended periods of time without any sanitation problems.Furthermore, the slug contains any unsanitary items within its plasticcovering. No other conventional method for handling plastic wastecombines the simplicity of the instant design with the ability toproduce dense slugs of plastic waste that are suitable for long termsanitary storage. Additional advantages and modifications will readilyoccur to those skilled in the art. Therefore, the invention in itsbroader aspects is not limited to the specific details, andrepresentative devices, shown and described herein. Accordingly, variousmodifications may be made without departing from the spirit or scope ofthe general inventive concept as defined by the appended claims andtheir equivalents. For example, while the preferred embodiment isdirected toward a mix of plastic waste typically encountered in a Navyenvironment, the apparatus and method can be modified to work on otherplastic mixes by adjusting the temperatures and pressures used.Additionally, a conventual shredding device can be added to theapparatus to shred the contaminated plastic waste prior to feeding thewaste into the chamber. The shredder permits large objects to be reducedin size so that they do not prevent compaction of the plastic waste.Such modifications are well within the ability of those skilled in theart without requiring undue experimentation.

What is claimed is:
 1. A compress/melt waste processor for processing afirst volume of contaminated plastic waste to produce a second volume ofa sanitary end product suitable for long-term storage, comprising:aframe; a chamber hatch mounted upon said frame; a chamber housing havingwalls, said chamber housing mounted upon said chamber hatch, whereinsaid housing walls and said chamber hatch define a chamber therein; aram movably disposed in said chamber, wherein said housing walls, saidchamber hatch and said ram define a space therebetween, and furtherwherein said ram and said housing walls define a gap therebetween forallowing steam to escape said chamber; means for feeding said firstvolume of contaminated plastic waste into said space; means mounted tosaid frame and operatively connected to said ram for compacting saidfirst volume of contaminated plastic waste, said compacting meansfunctioning to cause said ram to apply a first predetermined compactionpressure to the contaminated plastic waste to form a slug and to apply asecond predetermined compaction pressure to said slug; means for heatingsaid housing walls, said ram and said chamber hatch to a predeterminedtemperature sufficient to melt at least an outer layer of thecontaminated plastic waste without igniting the contaminated plasticwaste nor producing hazardous fumes associated with the burning of thecontaminated plastic waste and sufficient to cause an internaltemperature of said slug to exceed a predetermined internal temperaturewherein liquids trapped in the contaminated plastic waste are evaporatedout through said gap, said predetermined internal temperature beingmeasured at approximately a center of said slug; means for sensing saidcompaction pressures applied by said ram; means for detecting saidpredetermined internal temperature of said slug and said predeterminedtemperature of at least one of said housing walls, said ram and saidchamber hatch; and control means, responsive to input signals receivedfrom said pressure sensing means and said temperature detecting means,for controlling said compacting means and said heating means, saidcontrol means functioning to control said compacting means and saidheating means such that 1) said ram applies said predetermined firstcompaction pressure to said first volume of contaminated plastic waste,2) upon said predetermined first compaction pressure being obtained,said heating means is activated to heat said housing walls, said ram,and said chamber hatch to said predetermined temperature, 3) upon saidhousing walls, said ram, and said chamber hatch reaching saidpredetermined temperature, said ram applies said predetermined secondcompaction pressure to said slug, and 4) upon said predeterminedinternal temperature being exceeded, said heating means is deactivatedwhile said ram continuously compacts said slug at said predeterminedsecond compaction pressure until said melted outer layer of said slughas cooled sufficiently to harden, wherein said processor functions tocompact said first volume of contaminated plastic into a sanitary slugof said second volume and wherein a ratio of said first volume to saidsecond volume is about 30:1.
 2. A compress/melt waste processor asrecited in claim 1, wherein said heating means comprises electricresistive elements disposed within said ram, said chamber hatch and saidhousing walls.
 3. A compress/melt waste processor as recited in claim 1,wherein said heating means comprises electric resistive elementsdisposed around an outside surface of each of said ram, said chamberhatch and said housing walls.
 4. A compress/melt waste processor asrecited in claim 1, further comprising a means for cooling said housingwalls, said ram and said chamber hatch, and further wherein said controlmeans controls said cooling means such that upon said control meansdeactivating said heating means said control means activates saidcooling means.
 5. A compress/melt waste processor as recited in claim 4,wherein said cooling means includes tubes disposed within said ram, saidchamber hatch and said housing walls, said tubes having a cooling fluidpassing therethrough.
 6. A compress/melt waste processor as recited inclaim 4, wherein said cooling means includes tubes disposed around anoutside surface of each of said ram, said chamber hatch and said housingwalls, said tubes having a cooling fluid passing therethrough.
 7. Acompress/melt waste processor as recited in claim 1, wherein innersurfaces of said chamber hatch, said ram and said housing walls whichsurround said space are all formed from hard polished aluminum.
 8. Acompress/melt waste processor as recited in claim 1, wherein saidcompacting means comprises a linear actuator chosen from the groupconsisting of a hydraulic cylinder, a pneumatic cylinder, and ballscrews.
 9. A compress/melt waste processor as recited in claim 1,wherein said chamber hatch is slidably mounted upon said frame between afirst position defining said chamber and a second position laterallyremoved from said first position and defining an opening such that whensaid chamber hatch is at said first position said ram applies saidcompaction pressures to the contaminated plastic waste and when saidchamber hatch is at said second position said ram ejects said slug fromsaid chamber housing through said opening.
 10. A compress/melt wasteprocessor as recited in claim 1, wherein said compacting means functionsto compact the contaminated plastic waste to said first and secondpredetermined compaction pressures of between approximately 40 psi and50 psi.
 11. A compress/melt waste processor as recited in claim 1,wherein said compacting means functions to compact the contaminatedplastic waste to said first predetermined compaction pressure of betweenapproximately 40 psi and 50 psi and said second predetermined compactionpressure of approximately 20 psi.
 12. A compress/melt waste processor asrecited in claim 1, wherein said heating means functions to heat saidhousing walls, said ram, and said chamber hatch to said predeterminedtemperature of between approximately 325° F. to 350° F.
 13. Acompress/melt waste processor as recited in claim 1, wherein saidheating means functions to heat said slug to said predetermined internaltemperature of approximately 212° F.
 14. A compress/melt waste processorfor processing contaminated plastic waste to produce a sanitary endproduct suitable for long-term storage, comprising:a frame; a chamberhatch mounted upon said frame; a chamber housing having walls, saidchamber housing mounted upon said chamber hatch, wherein said housingwalls and said chamber hatch define a chamber therein; a ram movablydisposed in said chamber, wherein said housing walls, said chamber hatchand said ram define a space therebetween; means for feeding a firstvolume of contaminated plastic waste into said space; means operativelyconnected to said ram for compacting said first volume of contaminatedplastic waste into a second volume of contaminated plastic waste, saidcompacting means being an actuator functioning to cause said ram toapply a first predetermined compaction pressure of between approximately40 psi and 50 psi and a second predetermined compaction pressures ofbetween approximately 20 psi and 50 psi to the contaminated plasticwaste; means for heating said housing walls, said ram and said chamberhatch to a predetermined temperature of between approximately 325° F.and 350° F. wherein said heating functions to raise an internaltemperature of the contaminated plastic waste to a predeterminedinternal temperature at approximately a center of the contaminatedplastic waste of 212° F.; means for cooling said housing walls, said ramand said chamber hatch; a sensor for sensing said first and secondpredetermined compaction pressures applied by said ram; means fordetecting said predetermined internal temperature of the contaminatedplastic waste and said predetermined temperature of at least one of saidhousing walls, said ram and said chamber hatch; and control means,responsive to input signals received from said sensor and saidtemperature detecting means, for controlling said actuator and saidheating means such that 1) at times when the contaminated plastic wasteis fed into said space, said control means controls said actuator tocause said ram to apply said first compaction pressure to thecontaminated plastic waste, 2) upon said first compaction pressure beingobtained, and while continuing to cause said ram to compact thecontaminated plastic waste at said first compaction pressure, saidcontrol means activates said heating means to heat said housing walls,said ram, and said chamber hatch to said predetermined temperature, 3)upon said housing walls, said ram, and said chamber hatch reaching saidpredetermined temperature, and while continuing to cause said heatingmeans to heat said housing walls, said ram, and said chamber hatch atsaid predetermined temperature, said control means controls saidactuator such that said ram compacts the contaminated plastic waste atsaid second compaction pressure, and 4) upon the contaminated plasticwaste exceeding said predetermined internal temperature, said controlmeans deactivates said heating means and activates said cooling meanswhile continuing to control said actuator such that said ramcontinuously compacts the contaminated plastic waste until said housingwalls, said ram, and said chamber hatch cool to at least approximately140° F.
 15. A compress/melt waste processor as recited in claim 14,wherein said heating means comprises electric resistive elementsdisposed within said ram, said chamber hatch and said housing walls. 16.A compress/melt waste processor as recited in claim 14, wherein saidheating means comprises electric resistive elements disposed around anoutside surface of each of said ram, said chamber hatch and said housingwalls.
 17. A compress/melt waste processor as recited in claim 14,wherein said cooling means includes tubes disposed within said ram, saidchamber hatch and said housing walls, said tubes having a cooling fluidpassing therethrough.
 18. A compress/melt waste processor as recited inclaim 14, wherein said cooling means includes tubes disposed around anoutside surface of each of said ram, said chamber hatch and said housingwalls, said tubes having a cooling fluid passing therethrough.
 19. Acompress/melt waste processor as recited in claim 14, wherein saidchamber hatch is slidably mounted upon said frame between a firstposition defining said chamber and a second position laterally removedfrom said first position and defining an opening such that when saidchamber hatch is at said first position said ram acts to apply saidfirst and second compaction pressures to said first volume ofcontaminated plastic waste to form said second volume of contaminatedplastic waste wherein a ratio of said first volume to said second volumeis approximately 30:1 and when said chamber hatch is at said secondposition said ram acts to eject the contaminated plastic waste from saidchamber housing through said opening.